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For an efficient automotive AC system it is very essential to ensure uninterrupted and consistent airflow and temperature at the vent exit to help achieve the comfortable cabin space. This certainly requires temperature sensor to position at lowest possible temperature on heat exchanger and uniform flow distribution over it. However the uneven distribution of airflow on evaporator entry face leads to lowest temperature and sometimes goes undetected. This causes the condensate to get freezed and then frosting occurs at the core surface. Eventually a substantial portion of evaporator face gets choked and gradually airflow reduces and evaporator exit air temperature shoots up. Hence it is very important to prevent the frosting on evaporator core so to have uninterrupted airflow and adequate cooling in the passenger compartment. The present paper investigates the reasons for frosting occurring in one of the hatchback vehicle in bench test.

Radiators are types of heat exchangers, which are used to transfer the heat from one fluid to another fluid. It is mainly used in automobile engine cooling systems and the radiators are the major source of heat rejection from the system by cooling the working fluid (generally water or glycol mixture). The application of radiators in the two-wheeler vehicle segment plays a vital role in increasing engine efficiency by maintaining the optimum temperature inside the engine assembly. As the technology advances with higher power requirements for the two-wheeler vehicle segment, thermal management of combustion engine becomes a critical part of it, resulting in the advancement of radiator technology in terms of compactness and thermal performance. In order to cater to the increasing demand for high-powered engines, performance optimization of two-wheeler radiators becomes an important aspect of design.

Automotive heating ventilating and air conditioning (HVAC) noise is a very big concern for original equipment manufacturers (OEM) and suppliers. It turns out to be more challenging as the demand for acoustic comfort is increasing day by day. Many times an existing HVAC with some minor changes (mostly the vehicle fitment points) is proposed for face-lift vehicle but the performance expectation is far beyond the existing one due to market demand. One of the critical requirements is enhanced sound quality. To achieve that either experimental testing or numerical simulation is adopted. In either of these cases, it ends up with high number of experiments or increased simulation cost due to aero-acoustic simulation. Hence a combined approach is followed in order to investigate and improve the noise sources of an existing HVAC. The present paper describes this approach in details by doing numerical flow simulation followed by experimental investigation.

The aim of this paper is to optimize flow distribution on various ports of the ventilation unit. To improve the passenger comfort, ventilation unit need to be redesigned to get the uniform distribution in all ducts. There were challenges for the design modification on the unit to meet the distribution. The major challenge was to meet the distribution on the duct outlet without doing any design changes on the ducts. Hence the adapter which is the intermediate part between the blower and duct assembly is modified and simulation is done on the various design changes by changing the design of the adaptor part. CFD analysis is carried out on the ventilation unit with iterative design changes and achieved the target airflow and distribution. The analysis has been carried out on STAR CCM+ software.

A Finite Element Method (FEM) is used to determine the modal frequency and structural integrity of the automotive condenser assembly, whereas the experimentation (modal and dynamic) are performed using electro-dynamic vibration shaker for vibration durability. In this paper, numerical and experimental modal & dynamic analysis are discussed to derive the modal properties (mode shapes & modal frequencies) and dynamic properties (stresses & deflections) of condenser assembly. The effects of vibration occurring due to dynamic interaction between vehicle and road, vibration transmitted from machinery to its supporting structures thereby interfering with their performance, damage as well as malfunction and failure due to dynamic loading and cyclic loading. In this work, author compared modal frequencies as well as the life cycle of the condenser assembly through FEM and experimentations.

Maintaining thermal comfort is one of the key areas in vehicle HVAC design wherein airflow distribution inside the cabin is one of the important elements in deciding comfort sensation. However, the energy consumption of air conditioning system needs to stay within the efficient boundaries to efficiently cool down the passenger cabin otherwise the vehicle energy consumption may get worsened to a great extent. One approach to optimize this process is by using numerical methods while developing climate systems. The present paper focuses on the numerical study of cabin aiming and cabin cool-down of a passenger car by using computational fluid dynamics (CFD). The main goal is to investigate the cabin aiming with a view to figure out the minimum average velocity over the passengers at all vent positions. Cabin aiming ensures substantial amount of airflow reaches to the passengers as well as every corners of the cabin across the wide climatic range.

Transport sector comes under largest energy consuming category, after mining and other industries, a significant fuel economy improvement are required to reduce green house emission. Till now the most promising technologies in this attempt are electric vehicle. Electric vehicles use large batteries to store energy, most common battery used in electric vehicles are lithium ion and lithium polymer preferred due to their high energy density compared to weight. The flow of current causes heating in the battery cells, performance of Lithium-Ion battery cells is greatly impacted by their temperature. For optimum performance it should operate in desired temperature range (15°C-35°C). Battery cooling system is the system which maintain optimum temperature of battery by cooling/heating to increases the thermal efficiency of vehicle. Most common Battery Thermal Management methods used today are, Air Cooled, Indirect liquid Cooled and Direct Cooled.

High vehicle emission resulting in increasing the air pollution day by day has challenged and forced the automotive industry to look for alternate and more environment friendly technologies. The transformation of the automotive industry in near future towards green energy solutions has also fuelled the technological advancement in this industry. In order to fulfil this requirement, Electrical Vehicles (EVs) have emerged as the best solution available till now. It has become very popular because of the zero emission and higher wheel-drive efficiency. The vehicle has some limitations in terms of performance, cost, lifespan & battery safety. The EVs have lithium ion batteries incorporated to cater the drive power requirement. In order to maximize the vehicle performance, thermal management of the batteries becomes very critical. The battery thermal management system (BTMS) has crucial role in controlling the thermal behaviour of the batteries.

As the global warming due to carbon footprint is very alarming, vehicle emissions are getting stringent day by day. In such situation vehicle hybridization or fully electric vehicles are of obvious choices. However in any of the cases the battery cooling is a big concern area. As the heat produced by the battery need to be dissipated in the long run, it is of utmost need to develop and understand the battery cooling system. Present paper describes the experimental investigation of a battery cooling circuit. A complete bench comprising of both primary and secondary circuit is used for the testing. The primary circuit has a cooling unit with TXV, condenser and electric compressor run by high voltage. The secondary circuit consists of a chiller (integrated with TXV) unit responsible for battery cooling. The whole circuit typically resembles with one of dual air conditioning unit and uses one of known refrigerant used in vehicle AC system.

Automotive Air Conditioning is the process of removing the heat and moisture from the interior of an occupied space to improve comfort of occupants. A condenser is a device or unit used to condense refrigerant from its gaseous to its liquid state, by cooling it. In so doing, the latent heat is given up by the substance and transferred to the surrounding environment. It is made of Aluminum Alloy Material and subjected to very high internal stresses due to refrigerant pressure, thermal / inertia and dynamic load. In order to evaluate the structural integrity of the condenser assembly under these loading conditions, operating frequency should be far away from the resonance frequency and component design should be robust to sustain external excitation load coming from the engine & road. The above design evaluation criteria is also applicable for piston of AC’s reciprocating compressor.

A Automotive Air Conditioning is the process of removing heat and moisture from the interior of an occupied space to improve comfort of occupants. Heating, ventilation, and air conditioning (HVAC) is the technology of indoor and vehicular environmental comfort. Its goal is to provide thermal comfort and acceptable indoor air quality. HVAC systems can be used in both domestic and commercial environments. It is made of Plastic material and fitted inside the front dash panel, therefore, subjected to very high vibrations coming from engine & road. The main Objective is to remove unwanted vibrations by altering the modal frequency. From the FEA, very high deflection, cause unwanted vibrations reported on the HVAC assembly at low frequency (1st modal frequency) under dynamic conditions. Then, improved the design by adding the stiffeners on the flange to minimize that high deflection. Thereafter, modal frequency has been increased and reduced the high deflection.

The thermal heat load requirement for the cabin and the cockpit of aerial vehicle varies with various conditions comprises of altitudes and different weather conditions. The mapping of the heat load w.r.t. the above conditions is a complex phenomenon, which involves difficult mathematical modeling. The aerodynamic design of the aerial vehicle allows the flow of ambient air to contribute in the cabin and cockpit heat load along with passengers, pilots & co-pilots heat load at various weather conditions. The current study considers the mathematical modeling of the cabin and cockpit of aerial vehicle w.r.t. various weather conditions and altitudes and simulate the heat load requirements. The estimation of the heat load plays a key role in thermal management systems of the aerial vehicle for both the cabin and cockpit. The objective of this study is to highlight the importance of heat load requirement of the aerial vehicle and methods to simulate it.

Vehicles wind shield are designed to provide a clear visibility in winter as its one of the most important requirement for the comfortable and safe journey. In extreme winters, wind shield of vehicle is covered with layer of ice and if frosted happened, results in reduces the visibility distance. To increase the visibility and providing the comfort to driving the vehicle, heater is used in vehicle as an integrated part of vehicle HVAC System. When the blower air passes through heater, air temperature gets increased. When the hot air is injected through grill at designed angle of injection and at selected air velocity on wind shield surface, ice on wind shield melting due to convection heat transfer phenomenon and thus achieved a clear windshield glass and clear visibility at driver and at co-driver area.

Heating, ventilation and air conditioning systems play a crucial role in our day-to-day activities. With rise in global warming, leading to climate change, HVAC unit is the need of the hour. With average temperatures on the rise, it is quite imperative that the unit provides better thermal comfort to the passengers. Off-road vehicles like tractor, is also no exclusion. Tractor drivers have to experience adverse weather conditions out in the open field. Thus it is quite fundamental that sufficient airflow reaches every point inside the driver cabin, ensuring proper cool-down. To ensure proper distribution of airflow inside the cabin, optimization of HVAC unit needs to be properly carried out. The present study shows how an HVAC of an off-road vehicle is properly optimized with the help of Computational Fluid Dynamics. STAR-CCM+ v2021.2.1 is used as solver for the simulation.

The automotive industry is a gigantic industry as millions of vehicles are running on the road and it’s growing at a rapid rate. The emissions are causing various global problems such as global warming, green house effects, air pollutions etc. due to the use of fossil fuels in abundance. This drives to think for alternative solutions, which are eco-friendly and having less or no emissions. The electric vehicles (EVs) are the most reliable solution as it is having high performance and efficiency with zero emissions. The evolution of EVs has fuelled the two-wheeler EVs industry to flourish at a fast pace. Li-ion battery and traction motor are the most important components in two-wheeler EVs and the thermal management for battery is more important for higher efficiency with longer life and better reliability along with the traction motor to have long range and better durability.

In electric vehicles, along with cooling and heating requirement of battery, cabin atmosphere also need to be controlled according to human comfort level. Productivity level of humans decreases when cabin’s environment (including temperature, relative humidity and air velocity) varies too far from comfort range. For cold ambient conditions, waste heat from internal combustion engine is enough for heating passenger cabin in conventional vehicles. In contrast to that, electric vehicles do not have enough waste heat available to warm up cabin atmosphere during winters. Using battery power for heating in winters reduces vehicle mileage drastically. Consequently, many alternative cabin heating technologies and their combinations are proposed and designed to reduce the dependency on battery energy to improve thermal comfort under cold weather conditions.

As the current market trend is emerging towards the compactness, better comfort and less emission, it is quite important that factors contributing to these aspects should be kept under control and maintained within the desired range. Heating ventilation and air conditioning (HVAC) noise is one such factor which significantly contributes in occupants’ acoustic comfort. It creates discomfort to the occupants while HVAC is in operation and eventually lead to fatigue. In a HVAC, there are several different types and sources of noise which cumulatively impacts the overall noise level. However, few of them are quite prominent and has maximum impacts on overall noise. It is very important to identify and measure these sources in order to take appropriate countermeasure to mask or eliminate them. In order to identify and measure the noise sources, various methods are used.

The present paper outlines the selection and numerical modeling of a high performance and efficient blower motor fitted in an automotive Heating ventilation and air conditioning (HVAC) system. In today’s scenario blower motor is present in almost every car whether fitted with AC system or only blower system. The selection of a blower motor is very important in terms of delivering right amount of airflow with minimum consumption of electric power. As the power consumption goes up it may impacts in indirect green house gas (GHG) emission from a vehicle. While it does so e.g. fulfills HVACs’ airflow need, it generates some amount of heat which is very detrimental for its life and overall performance as well. Also the generated heat may lead to increase in temperature of the main stream air flow causing reduction in the cabin cooling and eventually hampers the comfort level.

The rapid evolution of electric vehicles (EVs) has considerably forced the automotive industry to design compact and highly efficient heat exchangers due to low-temperature applications. The plate type heat exchanger (Also known as “Chiller” in automotive industry) is one of the most important components in EVs thermal management systems. It is a type of heat exchanger, which uses metallic plates arranged like a staggered sandwiched structure and brazed together to exchange heat between two working fluids. The heat transfer between the plates occurs due to highly compact structural design as compare to any conventional heat exchangers. The chiller is having very large surface area, which is exposed to the working fluids as the distribution happens all across the plates. The chillers are more suitable design for transferring heat between ranges of working fluids pressure varying from low to high. Various types of welded, semi-welded plate heat exchangers are available in the market.

The heating, ventilation and air conditioning system is one of the complex systems installed inside the cabin of an automobile vehicle. Each HVAC discipline has specific design requirements in terms of packaging space, performance targets, etc. Technical specifications such as airflow, noise, air distribution, allowable leakage rate vary as per vehicle segment and interior design accordingly. While maintaining the design parameters of HVAC, design engineers often face challenges related to water leakage, air leakage, water infiltration, etc. Controlling these parameters becomes crucial for customer satisfaction and for safety features. Several studies on seal proof technology have been conducted and continue to be conducted, whether for air-based applications, water-based applications, or any other fluid material.The application of sealing technology is spread almost everywhere, from domestic purposes to industrial applications.